Applications of fusion-fluorescence imaging using indocyanine green in laparoscopic hepatectomy

[Laparoscopic Posterolateral Sectionectomy in Hepatocellular Cacinoma - Increasing Oncological Precision by Combining the Glissonean Pedicle Approach and Fluorescence Guidance]

AIM

Minimally invasive procedures have been increasingly performed in liver surgery. Benefits include lower intraoperative blood loss, reduced postoperative morbidity and shorter lengths of hospital stay in comparison to open liver surgery. Exact resection margins seem advantageous in primary liver cancer but challenging to implement with minimally invasive techniques. In this case report, we aimed to increase surgical precision by combining the Glissonean pedicle approach and intraoperative fluorescence guidance.

INDICATION

A 73-year-old female patient with CHILD A liver cirrhosis with chronic hepatitis C virus infection was transferred to our hospital with high levels of alpha-fetoprotein (792 ng/ml). Sectional imaging confirmed the suspected diagnosis of a single hepatocellular carcinoma (HCC) with a size of 2.2 cm in segments VI/VII. In line with the local tumour board recommendation, an anatomical posterolateral sectionectomy using the Glissonean pedicle approach was planned.

METHODS

The patient was placed in the French position. After mobilisation of the right liver, the posterolateral pedicle was encircled and transected. 0.2 mg/kg of body mass indocyanine green (ICG) was then injected intravenously. The perfused parenchyma of segments I-V and VIII turned green, but the unperfused posterolateral segment VI and VII remained native. The transection line was marked under ICG-imaging to indicate the transition of the posterolateral to the anteromedial sector. Parenchymal transection was performed under intermittent ICG-guided imaging. Pathological workup confirmed R0 resection of a well differentiated HCC in a cirrhotic liver (grade 4). The patient was discharged from the hospital on the 6th postoperative day after an uncomplicated course and was confirmed to be tumour-free six months after surgery.

CONCLUSION

As an additional intraoperative tool, ICG-imaging may provide visualisation of segment and sector boundaries and thus may enable precise anatomical resection. Prospective studies are needed to evaluate the added value of this technique, especially with regard to the rate of R0 resections.

Fluorescence imaging in the surgical management of liver cancers: Current status and future perspectives

Over the last decades, imaging technologies have got significant developments and become indispensable in the surgical management of liver cancers. Real-time navigation afforded by intraoperative images has a significant impact on the success of liver surgeries. Fluorescence imaging in the near-infrared spectrum has shown potential for tumor detection and image-guided surgery in clinics. While predominantly focused on indocyanine green (ICG) imaging, there is also accelerated development of more specific molecular tracers. Compared to passive targeting contrast agents ICG, active targeting and activatable probes both shed new light for intraoperative navigation owing to the higher degree of specificity for the tumor target. A variety of fluorescence imaging probes have been developed to target biomarkers unique to cancer cells or tumor microenvironment and demonstrated promising results. In this review, we provide a comprehensive update on preclinical development and clinical applications of fluorescence imaging in the surgical management of liver cancers. By highlighting the current status, we aim to offer insight into the challenges and opportunities for further investigation.

Tumor visualization and fluorescence angiography with indocyanine green (ICG) in laparoscopic and robotic hepatobiliary surgery - valuation of early adopters from Germany

Objectives

Indocyanine green (ICG) is a fluorescent dye which was initially used for liver functional assessment. Moreover, it is of value for intraoperative visualization of liver segments and bile ducts or primary and secondary liver tumors. Especially in minimally invasive liver surgery, this is essential to enhance the precision of anatomical guided surgery and oncological quality. As early adopters of ICG implementation into laparoscopic and robotic-assisted liver surgery in Germany, we summarize the current recommendations and share our experiences.

Methods

Actual strategies for ICG application in minimally invasive liver surgery were evaluated and summarized during a review of the literature. Experiences in patients who underwent laparoscopic or robotic-assisted liver surgery with intraoperative ICG staining between 2018 and 2020 from the Magdeburg registry for minimally invasive liver surgery (MD-MILS) were evaluated and the data were analyzed retrospectively.

Results

ICG can be used to identify anatomical liver segments by fluorescence angiography via direct or indirect tissue staining. Fluorescence cholangiography visualizes the intra- and extrahepatic bile ducts. Primary and secondary liver tumors can be identified with a sensitivity of 69-100%. For this 0.5 mg/kg body weight ICG must be applicated intravenously 2-14 days prior to surgery. Within the MD-MILS we identified 18 patients which received ICG for intraoperative tumor staining of hepatocellular carcinoma (HCC), cholangiocarcinoma, peritoneal HCC metastases, adenoma, or colorectal liver metastases. The sensitivity for tumor staining was 100%. In 27.8% additional liver tumors were identified by ICG fluorescence. In 39% a false positive signal could be detected. This occurred mainly in cirrhotic livers.

Conclusions

ICG staining is a simple and useful tool to assess individual hepatic anatomy or to detect tumors during minimally invasive liver surgery. It may enhance surgical precision and improve oncological quality. False-positive detection rates of liver tumors can be reduced by respecting the tumor entity and liver functional impairments.

Rapid fluorescence imaging of human hepatocellular carcinoma using the β-galactosidase-activatable fluorescence probe SPiDER-βGal

Fluorescence imaging of tumours facilitates rapid intraoperative diagnosis. Thus far, a promising activatable fluorescence probe for hepatocellular carcinoma (HCC) has not been developed. Herein, the utility of the fluorescence imaging of HCC using a β-galactosidase (β-Gal)-activatable fluorescence probe SPiDER-βGal was examined. β-Gal activity was measured in cryopreserved tissues from 68 patients. Live cell imaging of HCC cell lines and imaging of tumour-bearing model mice were performed using SPiDER-βGal. Furthermore, fluorescence imaging was performed in 27 freshly resected human HCC specimens. In cryopreserved samples, β-Gal activity was significantly higher in tumour tissues than in non-tumour tissues. Fluorescence was observed in HCC cell lines. In mouse models, tumours displayed stronger fluorescence than normal liver tissue. In freshly resected specimens, fluorescence intensity in the tumour was significantly higher than that in non-tumour liver specimens as early as 2 min after spraying. Receiver operating characteristic curves were generated to determine the diagnostic value of SPiDER-βGal 10 min after its spraying; an area under the curve of 0.864, sensitivity of 85.2%, and specificity of 74.1% were observed for SPiDER-βGal. SPiDER-βGal is useful for the rapid fluorescence imaging of HCC. Fluorescence imaging guided by SPiDER-βGal would help surgeons detect tumours rapidly and achieve complete liver resection.

Laparoscopic ultrasound-guided superselective portal vein injection combined with real-time indocyanine green fluorescence imaging and navigation for accurate resection of localized intrahepatic bile duct dilatation: a case report

Background

Primary intrahepatic bile duct dilatation can be very harmful to patients although it belongs to benign biliary disease. It can occur in any part of the liver, intraoperative laparoscopic ultrasound (LUS) guidance combine with real-time indocyanine green (ICG) fluorescence navigation are the means of choice for accurate surgical resection.

Case presentation

Herein we reported a 43-year-old female patient presented with repeated right upper abdominal pain and distension for 3 years and aggravated for half a year, without fever and jaundice. A diagnosis of localized bile duct dilatation with lithiasis in segment 4 (S4) was made on the basis of preoperative imaging. Correspondingly, we selected to perform a laparoscopic surgery with LUS guided real time ICG fluorescence imaging (ICG-FI) and navigation to make the operation more simply and accurately, as well as to retain normal tissues in a certain extent. Laparoscopic resection of S4b and partial S4a was successfully performed, without any complications.

Conclusion

Laparoscopic anatomical surgery for intrahepatic bile duct dilatation is a technically challenging operation. The combined use of preoperative three-dimensional computerized tomography (CT) planning, intraoperative LUS guided super-selection, ICG hepatic segment staining and real-time fluorescence navigation could help surgeons accurately complete the segmentectomy or subsegmentectomy with minimized trauma and maximized liver tissue preservation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12893-021-01325-w.

Consensus Guidelines for the Use of Fluorescence Imaging in Hepatobiliary Surgery

OBJECTIVE

To establish consensus recommendations for the use of fluorescence imaging with indocyanine green (ICG) in hepatobiliary surgery.

BACKGROUND

ICG fluorescence imaging has gained popularity in hepatobiliary surgery in recent years. However, there is varied evidence on the use, dosage, and timing of administration of ICG in clinical practice. To standardize the use of this imaging modality in hepatobiliary surgery, a panel of pioneering experts from the Asia-Pacific region sought to establish a set of consensus recommendations by consolidating the available evidence and clinical experiences.

METHODS

A total of 13 surgeons experienced in hepatobiliary surgery and/or minimally invasive surgery formed an expert consensus panel in Shanghai, China in October 2018. By the modified Delphi method, they presented the relevant evidence, discussed clinical experiences, and derived consensus statements on the use of ICG in hepatobiliary surgery. Each statement was discussed and modified until a unanimous consensus was achieved.

RESULTS

A total of 7 recommendations for the clinical applications of ICG in hepatobiliary surgery were formulated.

CONCLUSIONS

The Shanghai consensus recommendations offer practical tips and techniques to augment the safety and technical feasibility of ICG fluorescence-guided hepatobiliary surgery, including laparoscopic cholecystectomy, liver segmentectomy, and liver transplantation.

Artificial intelligence and guidance of medicine in the bubble

Microbubbles are nanosized gas-filled bubbles. They are used in clinical diagnostics, in medical imaging, as contrast agents in ultrasound imaging, and as transporters for targeted drug delivery. They can also be used to treat thrombosis, neoplastic diseases, open arteries and vascular plaques and for localized transport of chemotherapies in cancer patients. Microbubbles can be filled with any type of therapeutics, cure agents, growth factors, extracellular vesicles, exosomes, miRNAs, and drugs. Microbubbles protect their cargo from immune attack because of their specialized encapsulated shell composed of lipid and protein. Filled with curative medicine, they could effectively circulate through the whole body safely and efficiently to reach the target area. The advanced bubble-based drug-delivery system, integrated with artificial intelligence for guidance, holds great promise for the targeted delivery of drugs and medicines.

Indocyanine green staining for intraoperative perfusion assessment

Indocyanine green (ICG) is a fluorescent iodide-based dye which is used in hepatic surgery to evaluate the biliary tree, liver perfusion, and function. While liver perfusion assessment and delineation of anatomic regions has been performed using ultrasound, ischemic demarcation, or indigo carmine/methylene blue staining, ICG staining can overcome limitations associated with these techniques, such as rapid washout, lack of precision, non-demarcation in damaged livers, and lack of intraparenchymal fidelity. ICG can be used to fluoresce target segments/tumors (Positive staining) or counterstain normal liver tissue leaving areas of interest unstained (negative staining). Moreover, ICG enhancement patterns vary for different tumors, such as colorectal liver metastases vs. hepatocellular carcinoma, providing not only help with detection but also assessment of differentiation. In the field of oncology, benefits of ICG include detection of small radiographically occult tumors, distinction between cirrhotic nodules and cancer, identification of necrotic tumors in chemotherapy-damaged livers, and determining margins when intraoperative ultrasound is inadequate. While ICG has important and expanding indications in hepatic surgery, limitations include small depth of penetrance, need for special monitors/equipment, and potential for dye spillage. ICG is well tolerated, has a small learning curve, minimally invasive surgical integration, and options of both portal vein and peripheral vein injection and hence is a safe and versatile method of anatomic liver mapping, tumor visualization, and liver graft perfusion evaluation in oncologic surgery and liver transplantation. Advancements in technique and technology associated with ICG will aid in increasing the indications in hepato-biliary surgery.

A Novel Color-Coded Liver Metastasis Mouse Model to Distinguish Tumor and Adjacent Liver Segment

BACKGROUND

It is difficult to distinguish between a tumor and its liver segment with traditional use of indocyanine green (ICG) alone. In the present study, a method was used to limit ICG to the liver segment adjacent to a tumor. A spectrally-distinct fluorescently-labeled tumor-specific antibody against human carcinoembryonic antigen-related cell-adhesion molecules was used to label the metastatic tumor in a patient-derived orthotopic xenograft mouse model to enable color-coded visualization and distinction of a colon-cancer liver metastases and its adjacent liver segment.

MATERIALS AND METHODS

Nude mice received surgical orthotopic implantation in the liver of colon-cancer liver metastases derived from two patients. An anti- carcinoembryonic antigen-related cell-adhesion molecules monoclonal antibody (mAb 6G5j) was conjugated to a near-infrared dye IR700DX (6G5j-IR700DX). After three weeks, mice received 6G5j-IR700DX via tail-vein injection 48 hours before surgery. ICG was intravenously injected after ligation of the left or left lateral Glissonean pedicle resulting in labeling of the segment with preserved blood-flow in the liver. Imaging was performed with the Pearl Trilogy and FLARE Imaging Systems.

RESULTS

The metastatic liver tumor had a clear fluorescence signal due to selective tumor targeting by 6G5j-IR700DX, which was imaged on the 700 nm channel. The adjacent liver segment, with preserved blood-flow in the liver, had a clear fluorescence ICG 800 nm signal, while the left or left lateral segment had no fluorescence signal. Overlay of the images showed clear color-coded differentiation between the tumor fluorescing at 700 nm and the adjacent liver segment fluorescing at 800 nm.

CONCLUSIONS

Color-coding of a liver tumor and uninvolved liver segment has the potential for improved liver resection.

Hyperspectral enhanced reality (HYPER) for anatomical liver resection

BACKGROUND

Clinical evaluation of the demarcation line separating ischemic from non-ischemic liver parenchyma may be challenging. Hyperspectral imaging (HSI) is a noninvasive imaging modality, which combines a camera with a spectroscope and allows quantitative imaging of tissue oxygenation. Our group developed a software to overlay HSI images onto the operative field, obtaining HSI-based enhanced reality (HYPER). The aim of the present study was to evaluate the accuracy of HYPER to identify the demarcation line after a left vascular inflow occlusion during an anatomical left hepatectomy.

MATERIALS AND METHODS

In the porcine model (n = 3), the left branches of the hepatic pedicle were ligated. Before and after vascular occlusion, HSI images based on tissue oxygenation (StO2), obtained through the Near-Infrared index (NIR index), were regularly acquired and superimposed onto RGB video. The demarcation line was marked on the liver surface with electrocautery according to HYPER. Local lactates were measured on blood samples from the liver surface in both ischemic and perfused segments using a strip-based device. At the same areas, confocal endomicroscopy was performed.

RESULTS

After ligation, HSI demonstrated a significantly lower oxygenation (NIR index) in the left medial lobe (LML) (0.27% ± 0.21) when compared to the right medial lobe (RML) (58.60% ± 12.08; p = 0.0015). Capillary lactates were significantly higher (3.07 mmol/L ± 0.84 vs. 1.33 ± 0.71 mmol/L; p = 0.0356) in the LML versus RML, respectively. Concordantly, confocal videos demonstrated the absence of blood flow in the LML and normal perfusion in the RML.

CONCLUSIONS

HYPER has made it possible to correctly identify the demarcation line and quantify surface liver oxygenation. HYPER could be an intraoperative tool to guide perfusion-based demarcation line assessment and segmentation.

Identification of Glisson's Capsule Invasion During Hepatectomy for Colorectal Liver Metastasis by Contrast-Enhanced Ultrasonography Using Perflubutane

BACKGROUND

Glisson invasion by CLM is associated with a risk of margin-positive resection, leading to poor long-term outcomes after hepatectomy. This study was performed to evaluate the efficacy of intraoperative ultrasonography (IOUS) for the diagnosis of Glisson's capsule invasion by colorectal liver metastasis (CLM).

METHODS

This prospective study involved 50 consecutive patients undergoing hepatectomy for CLM. Preoperatively, all patients had undergone gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (EOB-MRI). During hepatectomy, a contrast agent (perflubutane) was intravenously injected and Glisson invasion was estimated based on three characteristic findings: a tumor thrombus, peripheral dilatation, and border irregularity/caliber change. The diagnostic abilities of the preoperative and intraoperative imaging studies were evaluated based on pathological examinations of resected specimens.

RESULTS

Among 187 CLMs resected, pathological examinations proved Glisson invasion in 24 tumors (13%). IOUS revealed a tumor thrombus in 3 tumors (1.6%), peripheral dilatation in 4 (2.1%), and border irregularity and/or caliber change in 24 (12.8%). The sensitivity and specificity of IOUS with any of the above three findings for diagnosis of Glisson invasion was 79% and 96%, respectively, while preoperative EOB-MRI detected Glisson invasion in only four tumors (sensitivity/specificity, 17%/100%). The cutoff value of caliber change for diagnosis of Glisson invasion was set at 140% by receiver operating characteristic analysis. The R0 resection rates were not significantly different between patients with (82%) and without (85%) Glisson invasion.

CONCLUSIONS

Identification of characteristic findings (tumor thrombus, peripheral dilatation, and border irregularity/caliber change) by contrast-enhanced IOUS is useful for the prediction of Glisson invasion by CLM.

Maltohexaose-indocyanine green (MH-ICG) for near infrared imaging of endocarditis

Infectious endocarditis is a life-threatening disease, and diagnostics are urgently needed to accurately diagnose this disease especially in the case of prosthetic valve endocarditis. We show here that maltohexaose conjugated to indocyanine green (MH-ICG) can detect Staphylococcus aureus (S. aureus) infection in a rat model of infective endocarditis. The affinity of MH-ICG to S. aureus was determined and had a Km and Vmax of 5.4 μM and 3.0 X 10⁻⁶ μmol/minutes/10⁸ CFU, respectively. MH-ICG had no detectable toxicity to mammalian cells at concentrations as high as 100 μM. The in vivo efficiency of MH-ICG in rats was evaluated using a right heart endocarditis model, and the accumulation of MH-ICG in the bacterial vegetations was 2.5 ± 0.2 times higher than that in the control left ventricular wall. The biological half-life of MH-ICG in healthy rats was 14.0 ± 1.3 minutes, and approximately 50% of injected MH-ICG was excreted into the feces after 24 hours. These data demonstrate that MH-ICG was internalized by bacteria with high specificity and that MH-ICG specifically accumulated in bacterial vegetations in a rat model of endocarditis. These results demonstrate the potential efficacy of this agent in the detection of infective endocarditis.

Augmented Reality during Open Liver Surgery Using a Markerless Non-rigid Registration System

INTRODUCTION

Intraoperative navigation during liver resection remains difficult and requires high radiologic skills because liver anatomy is complex and patient-specific. Augmented reality (AR) during open liver surgery could be helpful to guide hepatectomies and optimize resection margins but faces many challenges when large parenchymal deformations take place. We aimed to experiment a new vision-based AR to assess its clinical feasibility and anatomical accuracy.

PATIENTS AND METHODS

Based on preoperative CT scan 3-D segmentations, we applied a non-rigid registration method, integrating a physics-based elastic model of the liver, computed in real time using an efficient finite element method. To fit the actual deformations, the model was driven by data provided by a single RGB-D camera. Five livers were considered in this experiment. In vivo AR was performed during hepatectomy (n = 4), with manual handling of the livers resulting in large realistic deformations. Ex vivo experiment (n = 1) consisted in repeated CT scans of explanted whole organ carrying internal metallic landmarks, in fixed deformations, and allowed us to analyze our estimated deformations and quantify spatial errors.

RESULTS

In vivo AR tests were successfully achieved in all patients with a fast and agile setup installation (< 10 min) and real-time overlay of the virtual anatomy onto the surgical field displayed on an external screen. In addition, an ex vivo quantification demonstrated a 7.9 mm root mean square error for the registration of internal landmarks.

CONCLUSION

These first experiments of a markerless AR provided promising results, requiring very little equipment and setup time, yet providing real-time AR with satisfactory 3D accuracy. These results must be confirmed in a larger prospective study to definitively assess the impact of such minimally invasive technology on pathological margins and oncological outcomes.

Near-Infrared Fluorescence Imaging and Photodynamic Therapy for Liver Tumors

Surgery with fluorescence equipment has improved to treat the malignant viscera, including hepatobiliary and pancreatic neoplasms. In both open and minimally invasive surgeries, optical imaging using near-infrared (NIR) fluorescence is used to assess anatomy and function in real time. Here, we review a variety of publications related to clinical applications of NIR fluorescence imaging in liver surgery. We have developed a novel nanoparticle (indocyanine green lactosome) that is biocompatible and can be used for imaging cancer tissues and also as a drug delivery system. To date, stable particles are formed in blood and have an ~10–20 h half-life. Particles labeled with a NIR fluorescent agent have been applied to cancer tissues by the enhanced permeability and retention effect in animals. Furthermore, this article reviews recent developments in photodynamic therapy with NIR fluorescence imaging, which may contribute and accelerate the innovative treatments for liver tumors.

Evolving applications of fluorescence guided surgery in pediatric surgical oncology: A practical guide for surgeons

Fluorescence-guided surgery (FGS) is an increasingly available and popular method of visual field augmentation. The basic premise of FGS entails injection of fluorescent indocyanine green (ICG) and subsequent detection with a near-infrared (NIR) camera. For pediatric surgical oncologists, FGS remains experimental but is a promising modality for identifying tumor margins, locating metastases, performing sentinel lymph node biopsies, protecting peritumoral structures of interest, and facilitating reconstruction. Familiarity with basic ICG pharmacokinetics and NIR detection optics is critical for surgeons wishing to judiciously use FGS, as its success is firmly grounded in a thorough understanding of its capabilities and limitations. In this practical guide, we outline several well-described and innovative FGS applications by disease type, including their methods of administration, modes of detection, and typical ICG dosing paradigms. LEVEL OF EVIDENCE: V.

Real-Time Fluorescence Image-Guided Oncolytic Virotherapy for Precise Cancer Treatment

Oncolytic virotherapy is one of the most promising, emerging cancer therapeutics. We generated three types of telomerase-specific replication-competent oncolytic adenovirus: OBP-301; a green fluorescent protein (GFP)-expressing adenovirus, OBP-401; and Killer-Red-armed OBP-301. These oncolytic adenoviruses are driven by the human telomerase reverse transcriptase (hTERT) promoter; therefore, they conditionally replicate preferentially in cancer cells. Fluorescence imaging enables visualization of invasion and metastasis in vivo at the subcellular level; including molecular dynamics of cancer cells, resulting in greater precision therapy. In the present review, we focused on fluorescence imaging applications to develop precision targeting for oncolytic virotherapy. Cell-cycle imaging with the fluorescence ubiquitination cell cycle indicator (FUCCI) demonstrated that combination therapy of an oncolytic adenovirus and a cytotoxic agent could precisely target quiescent, chemoresistant cancer stem cells (CSCs) based on decoying the cancer cells to cycle to S-phase by viral treatment, thereby rendering them chemosensitive. Non-invasive fluorescence imaging demonstrated that complete tumor resection with a precise margin, preservation of function, and prevention of distant metastasis, was achieved with fluorescence-guided surgery (FGS) with a GFP-reporter adenovirus. A combination of fluorescence imaging and laser ablation using a KillerRed-protein reporter adenovirus resulted in effective photodynamic cancer therapy (PDT). Thus, imaging technology and the designer oncolytic adenoviruses may have clinical potential for precise cancer targeting by indicating the optimal time for administering therapeutic agents; accurate surgical guidance for complete resection of tumors; and precise targeted cancer-specific photosensitization.

Impact on operative outcomes of laparoscopic simultaneous resection of colorectal cancer and synchronous liver metastases

INTRODUCTION

The efficacy of laparoscopic simultaneous resection of primary colorectal cancer and synchronous colorectal liver metastases (SCRLM) remains unclear.

METHODS

We retrospectively evaluated data from 258 patients who had undergone simultaneous curative resection of the primary tumor and SCRLM from 2006 to 2017. We compared surgical outcomes between open, hybrid (laparoscopic colorectal resection and open hepatectomy), and pure laparoscopic approaches. Surgical outcomes were also evaluated between the open hepatectomy (OH) group (ie, open/hybrid surgery) and the laparoscopic hepatectomy (LH) group (ie, pure laparoscopic surgery) in 141 patients later in the study period (2013-2017), when the clinical indications for laparoscopic hepatectomy were restricted to simple wedge resection and/or left lateral sectionectomy in our center.

RESULTS

The pure laparoscopic approach was associated with significantly less intraoperative blood loss and a significantly shorter postoperative hospital stay than the open and hybrid approaches. Late in the study period, operative outcomes in the LH group (n = 37) were more favorable than for the OH group (n = 104) in terms of intraoperative blood loss and postoperative hospital stay. In patients with rectal cancer, however, earlier postoperative recovery in the LH group did not differ significantly from the OH group.

CONCLUSION

Laparoscopic simultaneous resection of SCRLM with the primary tumor by simple hepatectomy is safe and may enhance patients' postoperative recovery, especially in patients with colon cancer.

Application of Laparoscopic Technique in the Treatment of Hepatolithiasis

Hepatolithiasis is commonly encountered in Southeastern and East Asian countries, and its incidence is increasing in Western countries. For symptomatic hepatolithiasis or asymptomatic hepatolithiasis with signs of liver atrophy or malignancy, surgical intervention is needed, especially when peroral cholangioscopy and percutaneous transhepatic cholangioscopic lithotomy are not suitable or fail to be performed. Currently, laparoscopic surgery is gradually replacing traditional open surgery and becoming a better option. Various types of laparoscopic surgeries, including laparoscopic hepatectomy, laparoscopic biliary exploration through the common bile duct or the hepatic duct stump, and robotic-assisted laparoscopic surgery, have been developed for the treatment of simple hepatolithiasis, hepatolithiasis concomitant with choledocholithiasis, recurrent hepatolithiasis, and complicated hepatolithiasis. The related clinical experience is gradually accumulating. In this review, the laparoscopic applications and their advantages will be summarized. In most cases, the laparoscopic technique could provide the advantages of less trauma, reduced blood loss, and faster postoperative recovery.

Robotic hepatic resection in postero-superior region of liver

OBJECTIVE

Laparoscopic hepatectomy in the posterosuperior hepatic region is technically challenging and demanding. However, minimally invasive procedures carried out using the Da Vinci robot provide potential advantages in complex hepatectomy. This study reported the experience of a single center on robotic hepatectomy in the posterosuperior hepatic region.

METHODS

This retrospective study evaluated the general characteristics and perioperative outcomes of consecutive patients who underwent robotic hepatectomy in the posterosuperior hepatic region at our center from March 2015 to January 2020.

RESULTS

For 100 patients who were included into this study, 53 underwent anatomical segmentectomy or subsegmentectomy and 47 non-anatomical partial hepatectomy. There was no conversion to laparotomy. The R0 resection rate was 100%. The following perioperative outcomes were compared between patients who underwent anatomical segmentectomy/subsegmentectomy versus those who underwent non-anatomical partial hepatectomy: operation times of 160 versus 126 min, intraoperative blood losses of 100 versus 50 ml, intraoperative blood transfusion rates of 7.54% versus 4.26%, postoperative lengths of hospital stay of 5 versus 4 days, Clavien-Dindo Grade I-II complications rates of 15.09% versus 19.15%, Grade III-V complications rates of 3.77% versus 0%, bile leakage rates of 4% versus 7% and pleural effusion rates of also 4% versus 7%, respectively.

CONCLUSION

The results indicated the safety and feasibility of robotic anatomical and non-anatomical liver resections in the posterosuperior hepatic region. The robotic transabdominal approach is an option for hepatectomy in the posterosuperior hepatic region.

What is a precise anatomic resection of the liver? Proposal of a new evaluation method in the era of fluorescence navigation surgery

BACKGROUND/PURPOSE

Indocyanine green (ICG) fluorescence navigation has been adapted for anatomic liver resection (AR) but an objective method for evaluation of its validity is required. This pilot study aimed to propose a new method to evaluate the accuracy of parenchymal division along the plane between hepatic segments and estimate the real-time navigation efficacy for AR by the Medical Imaging Projection System (MIPS), which continuously demonstrates the transection plane using projection mapping with ICG fluorescence.

METHODS

Ten patients who underwent open AR using liver segmentation with ICG fluorescence technique between August 2016 and July 2019 were included: six patients under MIPS guidance (MIPS group), while four using only conventional ICG fluorescence technique before parenchymal resection (non-MIPS group). Densitometry of the captured fluorescence image was performed to evaluate the fluorescence area ratio of each transection plane. The accurate fluorescence area ratio was calculated by subtracting the fluorescence area rate on the resected side from that on the remnant side.

RESULTS

The accurate fluorescence area ratio of the MIPS group and the non-MIPS group was 23.0 ± 12.6% and 5.6 ± 9.5%, respectively (P = .038).

CONCLUSIONS

Based on the results of our new method, real-time navigation using the MIPS may facilitate performing AR along the plane between hepatic segments.

Laparoscopic anatomical liver resection guided by real-time indocyanine green fluorescence imaging: experience and lessons learned from the initial series in a single center

BACKGROUND

Anatomical liver resection is an established procedure for primary hepatic tumors. Laparoscopic anatomical hepatectomy has been proven to be technically achievable from S1 to S8 in experienced hands. The indocyanine green (ICG) fluorescence imaging technique offers a novel tool of intraoperative visualization in hepatobiliary surgery. This study aims to investigate the feasibility of laparoscopic anatomical liver resection based on segmental staining using real-time ICG fluorescence.

METHODS

From December 2015 to October 2017, 36 patients in our institute underwent lap-ALR using real-time ICG fluorescence mapping of the tumor-bearing portal territory. The procedural and perioperative data were collected and analyzed.

RESULTS

In our case series, we successfully performed the fashion of positive staining mostly in segmentectomy or sub-segmentectomy by individually injecting 5-10 ml of ICG (0.025 mg/ml) into its feeding portal branch guided by intraoperative ultrasound, and the negative staining mainly for sectionectomy, hemihepatectomy and multi-segmentectomy by interrupting the Glissonean pedicle serving the tumor-bearing segments and systemically injecting 1 ml of ICG (2.5 mg/ml). Our total successful rate of staining is 53%. No conversion to laparotomy, Clavien III-IV complication or 90-day mortality occurred. Valuable technical feedback, experience and lessons are learned from this initial practice.

CONCLUSIONS

Real-time ICG fluorescence imaging adds much precision to laparoscopic anatomical hepatectomy. The success of segmental staining requires a high proficiency of IOUS and skillful interpretation of preoperative 3D simulation. Decision-making on the fashions of positive and negative staining have been initially recommended. Multi-centered practice and technical modification are necessary to standardize its application.

Laparoscopic repeat liver resection for hepatic epithelioid hemangioendothelioma

BACKGROUND

Optimal treatment for patients with hepatic epithelioid hemangioendothelioma (HEHE) remains unclear. Laparoscopic repeat liver resection (LR) is a minimally invasive and potentially effective surgical option for multiple HEHEs.

CASE PRESENTATION

A 42-year-old woman with no relevant history was admitted for multiple liver tumors. Six tumors were observed on T2-weighted magnetic resonance imaging (MRI) including one in S2, two in S3, two in S7, and one in S8. Pathological evaluation of percutaneous tumor biopsy tissue suggested a diagnosis of HEHE and laparoscopic LR was planned. The procedure began with partial resection of S7 and partial resection of S8 and left lateral sectionectomy were performed. Another tumor was found intraoperatively on the surface of S6, necessitating removal by partial resection. Pathological evaluation of the resected tumor tissue from all seven tumors concurred with that of the preoperative biopsy. The patient was discharged on postoperative day 6 without any complications. A follow-up MRI 15 months after the primary surgery revealed one tumor each in S4, S6, and S8. Laparoscopic repeat LR was performed. The patient was discharged on postoperative day 5 without any complications. All three recurrent tumors were pathologically confirmed as HEHEs.

CONCLUSIONS

We successfully treated primary and recurrent HEHEs with laparoscopic LR, which is a reasonable minimally invasive procedure considering the possibility of multiple courses of liver surgery in patients with HEHE.

Fluorescence-guided hepatobiliary surgery with long and short wavelength fluorophores

Importance

Fluorescence-guided surgery (FGS) is a potentially powerful tool for hepatobiliary (HPB) surgery. The high sensitivity of fluorescence navigation is especially useful in settings where tactile feedback is limited.

Objective

The present narrative review evaluates literature on the use of FDA-approved fluorophores such as methylene blue (MB), 5-aminolevulinic acid (5-ALA), and indocyanine green (ICG) for clinical intra-operative image-guidance during HPB surgery.

Evidence Review

Approaches such as dosing, timing, imaging devices and comparative endpoints are summarized. The feasibility and safety of fluorophores in visualizing the biliary tree, identify biliary leaks, outline anatomic hepatic segments, identify tumors, and evaluate perfusion and graft function in liver transplants are discussed.

Findings

Tumor-specific probes are a promising advancement in FGS with a greater degree of specificity. The current status of tumor-specific probes being evaluated in clinical trials are summarized.

Conclusions and Relevance for Reviews

Relevant discussion of promising tumor-specific probes in pre-clinical development are discussed. Fluorescence-guidance in HPB surgery is relatively new, but current literature shows that the dyes are reliably able to outline desired structures with a variety of dosing, timing, and imaging devices to provide real-time intra-operative anatomic information to surgeons. Development of tumor-specific probes will further advance the field of HPB surgery especially during oncologic resections.

Demarcation Line Assessment in Anatomical Liver Resection: An Overview

Anatomical liver resection (ALR) is the preferred oncological approach for the treatment of primary liver malignancies, such as hepatocellular carcinoma and intrahepatic cholangiocarcinoma. The demarcation line (DL) is formed by means of selective vascular occlusion and is used by surgeons to guide ALR. Emerging intraoperative technologies are playing a major role to enhance the surgeon's vision and ensure a precise oncologic surgery. In this article, a brief overview of modalities to assess the DL during ALRs is presented, from the established conventional techniques to future perspectives.

On-Site Monitoring of Postoperative Bile Leakage Using Bilirubin-Inducible Fluorescent Protein

Background

Bile leakage is the most common postoperative complication associated with hepatobiliary and pancreatic surgery. Until now, however, a rapid, accurate diagnostic method for monitoring intraoperative and postoperative bile leakage had not been established.

Method

Bilirubin levels in drained abdominal fluids collected from 23 patients who had undergone hepatectomy (n = 22) or liver transplantation (n = 1) were measured using a microplate reader with excitation/emission wavelengths of 497/527 nm after applying 5 µM of UnaG to the samples. UnaG was also sprayed directly on hepatic raw surfaces in swine hepatectomy models to identify bile leaks by fluorescence imaging.

Results

The bilirubin levels measured by UnaG fluorescence imaging showed favorable correlations with the results of the conventional light-absorptiometric methods (indirect bilirubin: rs = 0.939, p < 0.001; direct bilirubin: rs = 0.929, p < 0.001). Approximate time required for bilirubin measurements with UnaG was 15 min, whereas it took about 40 min with the conventional method at a hospital laboratory. Following administration of UnaG on hepatic surfaces, the fluorescence imaging identified bile leaks not only on the resected specimens but also in the abdominal cavity of the swine hepatectomy models.

Conclusion

Fluorescence imaging techniques using UnaG may enable real-time identification of bile leaks during hepatectomy and on-site rapid diagnosis of bile leaks after surgery.

Electronic supplementary material

The online version of this article (10.1007/s00268-020-05774-x) contains supplementary material, which is available to authorized users.

A novel method of fluorescent imaging can guide hepatectomy for intrahepatic cholangiocarcinoma with intrahepatic biliary obstruction

OBJECTIVE

The aim of this study was to present a novel bile-duct obstructed area imaging (BOAI) and to investigate the feasibility and accuracy of this method in guiding hepatectomy for intrahepatic cholangiocarcinoma (ICC) with intrahepatic biliary obstruction.

METHODS

From May 2017 to October 2019, eligible patients who underwent hepatectomy guided by BOAI were enrolled. Perioperative outcomes and operative data were analyzed. To assess the feasibility of BOAI and Glissonean pedicle approach, demarcations based on them were compared. To verify the accuracy of BOAI staining of the target territory, simple linear regression analysis, and intraclass correlation coefficient were used to examine the relationship between predicted resected liver volume (PRLV) and actual resected liver volume (ARLV).

RESULTS

BOAI staining achieved valid demarcation in 15 (93.8%) of 16 patients, whereas the ischemic line achieved valid demarcation in only nine patients (57.3%; p = .017). ARLV and PRLV had a strong positive correlation (PRLV = 60.06 + 0.925 × ARLV; R = .945; p = .000). Meanwhile, ARLV (intraclass correlation coefficient = .971) achieved an excellent agreement with PRLV (p < .001).

CONCLUSIONS

The novel BOAI staining method can provide valid, feasible, and accurate demarcation line and may be an effective method in the surgical treatment of intrahepatic biliary obstruction.

Precision Liver Resection: Three-Dimensional Reconstruction Combined with Fluorescence Laparoscopic Imaging

Liver surgery has entered the era of precision surgery. Therefore, how to optimize the resection of lesions and reduce the unnecessary time of liver ischemia and hypoxia have become the focus. A total of 11 patients who underwent fluorescence laparoscopic liver mass resection and preoperative three-dimensional (3D) reconstruction between August 2018 and July 2020 were evaluated. Liver cirrhosis occurred in 3 patients. The mean intraoperative blood loss was 166.8 ± 105.7 mL. The average length of the operation time was 152.0 ± 45.3 minutes. The average intraoperative hilar occlusion time was 9.3 minutes (except for hilar cholangiocarcinoma). The liver function of all patients, except patients with hilar bile duct carcinoma, returned to the preoperative level at 72 hours, and no serious complications occurred. 3D reconstruction combined with fluorescence laparoscopic imaging is safe and effective for precision liver resection.

Simultaneous visualization of pulmonary nodules and intersegmental planes on fluorescent images in pulmonary segmentectomy

OBJECTIVES

The technique of simultaneously visualizing pulmonary nodules and the intersegmental plane using fluorescent images was developed to measure the distance between them intraoperatively.

METHODS

Patients who underwent pulmonary segmentectomy were consecutively included in this study between March 2016 and July 2019. Computed tomography or electromagnetic bronchoscopy-guided localization with indocyanine green-lipiodol emulsion was performed on the day of surgery. In the middle of the surgery, after dividing the segmental artery, vein and bronchus to a targeted segment, 0.3-0.5 mg/kg of indocyanine green was injected intravenously.

RESULTS

In total, 31 patients (17 men and 14 women with a mean age of 63.2 ± 9.8 years) were included in this study. The mean size and depth of the nodules were 1.2 ± 0.5 (range 0.3-2.5) cm and 16.4 ± 9.9 (range 1.0-42.0) mm, respectively. Pulmonary nodules and intersegmental plane of all the patients were visualized using a fluorescent thoracoscope. The resection margins were more than the size of the tumour or were 2 (mean 2.4 ± 1.2) cm in size in all patients except one. The resection margin of this patient looked sufficient on the intraoperative view. However, adenocarcinoma in situ at the resection margin was identified based on the pathological report. The mean duration of the operation was 168.7 ± 53.3 min, and the chest tube was removed on an average of 4.7 ± 1.8 days after surgery in all patients.

CONCLUSIONS

The dual visualization technique using indocyanine green could facilitate an easier measurement of the distance between pulmonary nodules and the intersegmental plane during pulmonary segmentectomy.

Evolution of photodynamic medicine based on fluorescence image-guided diagnosis using indocyanine green and 5-aminolevulinic acid

New diagnostic techniques based on photodynamic medicine, such as near-infrared fluorescence using indocyanine green (NIR-ICG) and 5-aminolevulinic acid-mediated photodynamic diagnosis (ALA-PDD), are aiding navigation tasks across various fields of surgery. Specifically, NIR-ICG is being used for the intraoperative identification of sentinel lymph nodes or blood vessels in organ resection and for blood flow evaluation in surgery. These ICG-fluorescent imaging techniques could provide an additional and potentially valuable way to identify vascular and lymphatic structures in surrounding tissue. 5-Aminolevulinic acid is a precursor of a photosensitizing substance with affinity for tumors; thus, diagnostic laparoscopy using ALA-PDD in combination should improve the accuracy of detecting peritoneal dissemination in patients with advanced gastric cancer. The ability to overlay fluorescent imaging with conventional color images in real time using ALA-PDD and NIR with ICG would be of immense benefit to surgeons, providing good visualization and detection of target lesions not seen with the naked eye. A multi-center clinical study examining the safety and efficacy of ALA-PDD during laparoscopic examination for patients with advanced gastric cancer is currently underway in the form of doctor-initiated trials, and further verification studies will be conducted. Such imaging capability could have broad potential across cancer and vascular surgery.

Intraoperative Imaging Techniques to Visualize Hepatic (Micro)Perfusion: An Overview

The microcirculation plays a crucial role in the distribution of perfusion to organs. Studies have shown that microcirculatory dysfunction is an independent predictor of morbidity and mortality. Hence, assessment of liver perfusion offers valuable information on the (patho)physiological state of the liver. The current review explores techniques in perfusion imaging that can be used intraoperatively. Available modalities include dynamic contrast-enhanced ultrasound, handheld vital microscopes, indocyanine green fluorescence angiography, and laser contrast speckle imaging. Dynamic contrast-enhanced ultrasound relays information on deep tissue perfusion and is a commonly used technique to assess tumor perfusion. Handheld vital microscopes provide direct visualization of the sinusoidal architectural structure of the liver, which is a unique feature of this technique. Intraoperative fluorescence imaging uses indocyanine green, a dye that is administered intravenously to visualize microvascular perfusion when excited using near-infrared light. Laser speckle contrast imaging produces non-contact large surface-based tissue perfusion imaging free from movement- or pressure-related artefacts. In this review, we discuss the intrinsic advantages and disadvantages of these techniques and their clinical and/or scientific applications.

Current status of laparoscopic liver resection for the management of colorectal liver metastases

Colorectal cancer (CRC) is one of the most prevalent malignancies worldwide. The commonest site of spread is the liver, with up to 40% of patients developing colorectal liver metastasis (CLRM) during the course of their lifetime. Significant advances in surgical techniques, as well as breakthroughs in chemotherapy and biologic agents, have resulted in dramatic improvements in prognosis. A multimodal approach comprising of liver resection coupled with systemic therapy offers these patients the best chance of cure. The arrival of laparoscopic liver resection (LLR) within the last 3 decades has added a whole new dimension to the management of this condition. Today, CLRM is one of the most frequent indications for LLR globally. Meta-analyses of retrospective studies and two randomized trials have demonstrated superior short-term outcomes following LLR, with no differences in mortality rates. Oncologically, R0 resection rates are comparable to the open approach, while overall and disease-free survival rates are also similar. As surgeons gain confidence, boundaries are pushed even further. High-volume centers have published their early experiences with complex LLR of recurrent CLRM as well as totally laparoscopic synchronous resection of CRC and liver metastases, with very encouraging results. In the presence of extensive bilobar CLRM, two-stage hepatectomy (TSH) and associating liver partition with portal vein ligation (ALPPS) may be adopted to augment an inadequate future liver remnant to facilitate metastasectomy. Interestingly, the adoption of LLR for these techniques also seem to confer additional benefits. Despite the plethora of advantages, LLR comes with its own unique set of limitations such as a steep learning curve and high cost. The surgical world eagerly awaits the results of prospective trials currently underway in order to further advance the management of this disease.

Robotic approach to the liver: Open surgery in a closed abdomen or laparoscopic surgery with technical constraints?

The application of the minimally invasive approach has shown to be safe and effective for liver surgery and is in constant growth. The indications for laparoscopic surgery are steadily increasing across the field. In the early 2000s, robotic surgery led to some additional improvements, such as tremor filtration, instrument stability, 3D view and more comfort for the surgeon. These techniques bring in some advantages compared to the traditional OLR: less blood loss, shorter admissions, fewer adhesions, and a faster postoperative recovery and better outcomes in case of further hepatectomy for tumor recurrence has been shown. Concerning which is the best minimally invasive approach between laparoscopic and robotic surgery, the evidence is still conflicting. The latter shows good potential, since the endo-wristed instruments work similarly to the surgeon's hands, even with an intact abdominal wall. However, the technique is still under development, burdened by important costs, and limited by the lack of some instruments available for the laparoscopic approach. The paucity of universally accepted and proven data, especially concerning long-term outcomes, hampers drawing univocal acceptance at present. Furthermore, the number of variables related both to the patient and the disease further complicates the decision leading to a treatment tailored to each patient with strict selection. This review aims to explore the main differences between laparoscopic and robotic surgery, focusing on indications, operative technique and current debated clinical issues in recent literature.

Progress in hepatectomy for hepatocellular carcinoma and peri-operation management

The global incidence of liver cancer continues to grow. Liver cancer, especially hepatocellular carcinoma, has high recurrence and mortality rates. Here, we review the past decade's diagnostic, therapeutic, and management strategies for hepatocellular carcinoma, and summarize new patient management approaches, including enhanced recovery after surgery, targeted therapy, and immunotherapy. We compare traditional and innovative management methods, which comprise developments in precision medicine, and consider their limitations. Ongoing innovation and technological advances enable surgeons to gain deeper understandings of the multidimensionality of hepatocellular carcinoma, thereby promoting the continuous development of precision therapy.

Precise right hemihepatectomy for the treatment of hepatocellular carcinoma guided by fusion ICG fluorescence imaging

To evaluate the clinical significance of fusion indocyanine green (ICG) fluorescence imaging in precise right hemihepatectomy for the treatment of hepatocellular carcinoma (HCC). 47 patients with HCC who underwent right hemihepatectomy were retrospectively analyzed. 18 of them guided by fusion ICG fluorescence imaging (FIGFI) while 29 patients underwent conventional right hepatectomy without guidance. Compared to the patients with conventional treatment, the intraoperative blood loss of the patients with guided surgery was significantly less, and no transfusion and hepatic occlusion were performed during the operation. Liver function recovery faster in guided group. The incidence of postoperative complications is also lower, and the recurrence rate in one year is significantly reduced. ICG fluorescence range of 18 patients in liver surface was consistent with the ischemic line, and their postoperative liver cross-sections were clearly demarcation. There were no significant differences in the mean operation time, blood loss, postoperative hospital stays, cases of blood transfusion, complication rate, or postoperative peak volume of ALT and TB between positive or negative staining groups. Pathology results of all patients demonstrated HCC and negative margins, and microvascular invasion occurred in 8 cases. The average follow-up time of 18 patients was 16.7 months, and recurrence was found in 5 cases after surgery. FIGFI could guide the anatomical right hepatectomy with real -time increased radical rate, accuracy and safety for the treatment of HCC, and therefore showed a promising prospect.

Advances in resection and transplantation for hepatocellular carcinoma

It would be impossible to summarise all of the significant developments in the surgical management of hepatocellular carcinoma (HCC), even just over the past year, in a manuscript of this scope. Thus, we have selected topics for discussion that are the subject of current controversy and have attempted to present balanced points of view. Hepatic resection and transplantation are both mature modalities, and for the most part technical advances and improvements in candidate selection are incremental. The ability to readily cure hepatitis C stands out as the most impactful development in the field over recent years, especially in Western countries where hepatitis C has long been the chief aetiology underlying HCC and a predictor of poor outcomes after surgery, but its full implications remain to be clarified. The rising incidence of non-alcoholic steatohepatitis-related HCC and what it means with regard to surgical HCC management is an area of great current interest. With advancing technology, non-surgical locoregional treatments are gaining increasing application as potentially curative therapies. In addition, the advances in molecular and genomic assessment of HCC hold promise for personalising treatment and prognostication. The possible role of immunotherapy as an adjuvant to resection is being aggressively investigated. While liver surgery maintains an important role, the care of patients with HCC is more and more a team effort and needs to take place in the context of a well-integrated interdisciplinary programme to achieve the best outcomes for patients.

Laparoscopic anatomical liver resection using indocyanine green fluorescence imaging

BACKGROUND

Anatomical liver resections guided by a demarcation line after portal staining or inflow clamping of the target area have been established as essential methods for curative treatment of hepatocellular carcinoma (HCC) and have subsequently been applied to other malignancies. However, laparoscopic anatomical liver resection (LALR) procedures are very difficult to reproduce, and the confirmation of demarcation of the hepatic segment on a monitor is also challenging. Recently, indocyanine green (ICG) fluorescence imaging has been used to identify hepatic tumors and segmental boundaries during hepatectomy. Herein, we describe LALR using ICG fluorescence imaging.

METHODS

Three patients underwent pure LALR using ICG fluorescence imaging at our institute. One patient underwent anatomical partial liver resection for HCC, another underwent segmentectomy 3 for metastatic liver cancer, and the third underwent right anterior sectionectomy for HCC. To visualize hepatic perfusion and the demarcation line by negative staining using an optical imaging system, 2.5 mg ICG was injected intravenously during surgery following clamping or closure of the proximal Glissonean pedicles.

RESULTS

For all three cases, ICG fluorescent imaging clearly delineated the demarcation lines and allowed identification of intersegmental planes to some extent because the tumor-bearing hepatic region became non-fluorescing parenchyma during parenchymal transection. This allowed surgeons to recognize the direction and guide the transection of the liver parenchyma when performing LALR.

CONCLUSION

LALR using ICG fluorescence imaging is a feasible procedure for resection of the tumor-bearing hepatic region and facilitates visualization of the demarcation line and identification of the boundaries of the hepatic sections.

[Three-dimensional visualization combined with indocyanine green fluorescence imaging in diagnosis and treatment of primary hepatocellular carcinoma]

OBJECTIVE

To explore the value of three-dimensional visualization technology (3DVT) combined with indocyanine green (ICG) fluorescence imaging in the diagnosis and treatment of primary hepatocellular carcinoma (HCC).

METHODS

We retrospectively analyzed the clinical data of 154 patients with HCC admitted to the Department of Hepatobiliary Surgery, Zhujiang Hospital, Southern Medical University between January, 2016 and November, 2018. In 57 of the patients (3DVT group), preoperative CT and Gd-EOB-DTPA-enhanced MRI were performed and 3D visualization and surgical planning was carried out before the operation; intraoperative ICG florescence imaging was performed for real-time detection of the tumor location and demarcation, intrahepatic satellite lesions and metastases. According to the intraoperative fluorescent signals and 3D visualization-based surgical planning, the final surgical plan was determined. In the other 97 patients (control group), conventional surgical assessment and surgical resection of the tumor was carried out. The preoperative imaging findings, intraoperative tumor detection, postoperative laboratory results, pathological reports, and follow-up data of the patients were analyzed.

RESULTS

In 3DVT group, 63 and 70 lesions were detected by preoperative CT and MRI, respectively; compared with CT examination, intraoperative ICG florescence imaging revealed additional 17 lesions, among which 10 were pathologically confirmed as HCC and 7 as cirrhosis nodules. The median volume of bleeding was 300 mL in 3DVT group, significantly less than that in the control group (400 mL; Z=2.291, P=0.022). In both groups, serious complications or perioperative death occurred in none of the patients. The incidence of postoperative complications was significantly lowed in 3DVT group than in the control group [21% (12/57) vs 48.4% (47/97); χ2=11.406, P=0.001]. The overall disease-free survival rate at 2 years after the operation was significantly higher in 3DVT group than in the control group (74.9% vs 28.9%, P=0.022).

CONCLUSIONS

3DVT combined with ICG fluorescence imaging allows precise preoperative diagnosis, surgical planning and implementation, intraoperative detection of small liver cancers and precise navigation for HCC treatment, thereby helping to reduce postoperative complications and improve the disease-free survival rate of the patients.

Endoscopic Fluorescence-Guided Surgery for Sinonasal Cancer Using an Antibody-Dye Conjugate

OBJECTIVE

Endoscopic resection of sinonasal squamous cell carcinoma has become the standard of care, but challenges remain in obtaining clear resection margins. The current study evaluated the feasibility of endoscopic fluorescence-guided surgery (FGS) to improve surgical resection in a human sinus surgical model.

METHODS

A fluorescence endoscope optimized for near-infrared (NIR) fluorescence detection was evaluated in a phantom study. Various endoscope diameters (4 and 10 mm) and viewing angles (0, 30, and 45 degrees) were evaluated to determine the sensitivity of the system for IRDye800CW detection at various working distances (1-5 cm). Endoscopic FGS was then validated in a three-dimensional human sinus surgical model to which squamous cell tumors derived from mice were inserted. Mice had received intravenous panitumumab-IRDye800CW and upon fluorescence-guided tumor resection, mean fluorescence intensity (MFI) and tumor-to-background ratio (TBR) were calculated in in situ and ex vivo settings.

RESULTS

A significantly higher fluorescence intensity was found when using the 10-mm diameter endoscope compared to the 4mm diameter endoscope (P < .001). No significant difference in MFI was found among the viewing angles of the 4-mm diameter endoscope. Using the human sinus model, the highest MFI and TBR were obtained at a 1-cm working distance compared to longer working distances.

CONCLUSION

We demonstrate that clinically acceptable TBRs were obtained with several working distances to discriminate tumor tissue from adjacent normal tissue in a human sinus model, and that endoscopic FGS may have great potential in identifying residual tumor tissue regions during surgery. Laryngoscope, 2019.

Novel method of intraoperative liver tumour localisation with indocyanine green and near-infrared imaging

INTRODUCTION

Fluorescence imaging (FI) with indocyanine green (ICG) is increasingly implemented as an intraoperative navigation tool in hepatobiliary surgery to identify hepatic tumours. This is useful in minimally invasive hepatectomy, where gross inspection and palpation are limited. This study aimed to evaluate the feasibility, safety and optimal timing of using ICG for tumour localisation in patients undergoing hepatic resection.

METHODS

From 2015 to 2018, a prospective multicentre study was conducted to evaluate feasibility and safety of ICG in tumour localisation following preoperative administration of ICG either on Day 0-3 or Day 4-7.

RESULTS

Among 32 patients, a total of 46 lesions were resected: 23 were hepatocellular carcinomas (HCCs), 12 were colorectal liver metastases (CRLM) and 11 were benign lesions. ICG FI identified 38 (82.6%) lesions prior to resection. The majority of HCCs were homogeneous fluorescing lesions (56.6%), while CLRM were homogeneous (41.7%) or rim-enhancing (33.3%). The majority (75.0%) of the lesions not detected by ICG FI were in cirrhotic livers. Most (84.1%) of ICG-positive lesions detected were < 1 cm deep, and half of the lesions ≥ 1 cm in depth were not detected. In cirrhotic patients with malignant lesions, those given ICG on preoperative Day 0-3 and Day 4-7 had detection rates of 66.7% and 91.7%, respectively. There were no adverse events.

CONCLUSION

ICG FI is a safe and feasible method to assist tumour localisation in liver surgery. Different tumours appear to display characteristic fluorescent patterns. There may be no disadvantage of administering ICG closer to the operative date if it is more convenient, except in patients with liver cirrhosis.

Laparoscopic Repeat Hepatic Resection for the Management of Liver Tumors

BACKGROUND

Laparoscopic hepatic resection has been developed as a minimally invasive surgery; however, laparoscopic repeat minor hepatic resection (LRH) carries a higher risk of damage to other organs because of postoperative changes to and losses of anatomical landmarks. The current standard approach at many facilities has been to perform open repeat minor hepatic resection (ORH). This paper describes the surgical outcomes, procedure safety, and utility of ORH versus LRH, as well as the laparoscopic techniques used in LRH.

METHODS

Between February 2010 and May 2018, the data of 142 patients who underwent LRH or ORH at a single institution were retrospectively reviewed. Surgical outcomes, procedure safety, and procedure utility data were analyzed.

RESULTS

Forty-five patients underwent LHR and 97 patients underwent ORH. The conversion rate from LHR to OHR was 13.3%. After propensity score matching (PSM), the estimated blood loss was significantly lower in the LRH group than in the ORH group (50 mL vs. 350 mL; P < 0.001). The LRH group had an 8.1% complication rate, while the ORH group had a complication rate of 24.3% (P = 0.044). The postoperative length of stay was significantly shorter in the LHR group than in the OHR group (9 days vs. 11 days) (P = 0.024).

CONCLUSION

LRH can be performed safely using various surgical devices. More favorable results are achieved with LRH than with ORH in terms of surgical outcomes including intraoperative bleeding, postoperative complications, and postoperative lengths of stay.

The Application of Indocyanine Green (ICG) Staining Technique During Robotic-Assisted Right Hepatectomy: with Video

INTRODUCTION

The application of indocyanine green (icg) properties in the field of HPB surgery is gaining momentum. The adoption of the staining technique for the visualization of hepatic liver parenchyma is still preliminary.

METHODS

We performed a 1:1 case- matched comparison among 20 patients who underwent robotic liver resection with or without the application of icg fluorescence.

RESULTS

The icg enabled the reduction of postoperative liver abscess and bile leakage rate. The staining technique was not time-consuming and provided excellent enhancement of liver transection line.

CONCLUSION

The routine use of icg-fluorescence could potentially reduce the postoperative complications during robotic liver surgery.

Laparoscopic hepatectomy for liver metastasis of lung large-cell neuroendocrine carcinoma: A case report

INTRODUCTION

Lung large-cell neuroendocrine carcinoma (LCNEC) is an aggressive and a rare type of lung cancer, and the prognosis of LCNEC with distant metastasis is extremely poor, with a five-year survival rate of 0%. Here, we report a case of laparoscopic hepatectomy for liver metastasis of lung LCNEC.

PRESENTATION OF CASE

A 63-year-old man received a routine physical examination, and abnormal chest radiographic findings were observed; chest computed tomography (CT) in our hospital revealed that the patient had left pneumothorax and a lesion measuring 18 mm in the inferior lingular segment of the lung. The patient underwent thoracoscopic lobectomy, and the final pathological diagnosis was lung LCNEC. Four years after surgery, abdominal CT revealed a mass measuring 27 mm in the liver. The patient underwent laparoscopic partial hepatectomy, and postoperative pathological examination showed liver metastasis of LCNEC. There was no sign of recurrence 6 months after hepatectomy.

DISCUSSION

LCNEC with distant metastasis has a poor response to systemic chemotherapy, and the median survival time of patients with distant metastasis is estimated to be approximately 6 months, with a five-year survival rate of 0%. Although the common site of metastasis from LCNEC is the liver, there are no previous reports of hepatectomy for liver metastasis of LCNEC.

CONCLUSION

We report a case of laparoscopic hepatectomy for liver metastasis of lung LCNEC. It is suggested that surgical resection for solitary distant metastasis of LCNEC may improve prognosis.

Effectiveness and safety of indocyanine green fluorescence imaging-guided hepatectomy for liver tumors: A systematic review and first meta-analysis

BACKGROUND

This meta-analysis was conducted to evaluate the effectiveness and safety of indocyanine green fluorescence imaging-guided hepatectomy(FIGH) for liver tumors.

METHODS

Clinical studies were retrieved from the PubMed, Embase, Cochrane Library, Medline and Web of Science electronic databases. Primary outcomes included operative time, blood loss, blood transfusion, hospital stay, R0 resection, postoperative complications, postoperative mortality and 1-year recurrence rate. Study-specific effect sizes and their 95% confidence intervals (CIs) were combined to calculate the pooled value using a fixed-effects or random-effects model.

RESULTS

Six studies comprising 587 patients were included. Major operative time (mean difference [MD] = -55.45; 95% CI = -78.85- -32.05), blood loss (MD = 12.99; 95% CI = 12.00-13.97), hospital stay (rate difference [RD] = -12.61; 95% CI = -15.06- -10.17), and postoperative complications (RD = -0.07; 95% CI = -0.12- -0.01) were all less in the FIGH group than in the traditional hepatectomy(TH) group. No differences were found in blood transfusion, R0 resection or 1-year recurrence rate. No perioperative mortality was observed in either group.

CONCLUSION

Based on current evidence, applying indocyanine green fluorescence imaging technology to accurately diagnose and treat liver tumors can effectively reduce operative time, blood loss, hospital stay and postoperative complications.

The Application of Indocyanine Green Fluorescence Imaging During Robotic Liver Resection: A Case-Matched Study

BACKGROUND

The ICG fluorescence properties are progressively gaining momentum in the HPB surgery. However, the exact impact of ICG application on surgical outcomes is yet to be established.

METHODS

Twenty-five patients who underwent ICG fluorescence-guided robotic liver resection were case-matched in a 1:1 ratio to a cohort who underwent standard robotic liver resection.

RESULTS

In the ICG group, six additional lesions not diagnosed by preoperative workup and intraoperative ultrasound were identified and resected. Four of the lesions were proved to be malignant. Despite the similar operative time (288 vs. 272 min, p = 0.778), the risk of postoperative bile leakage (0% vs. 12%, p = 0.023), R1 resection (0% vs. 16%, p = 0.019) and readmission (p = 0.023) was reduced in the ICG group compared with the no-ICG group.

CONCLUSIONS

The ICG fluorescence is a real-time navigation tool which enables surgeons to enhance visualization of anatomical structures and overcome the disadvantages of minimally invasive liver resection. The procedure is not time-consuming, and its applications can reduce the postoperative complication rate in robotic liver surgery.